Computer back panel portion



FIG. 1 is an isometric view of a computer back panel showing my new design;

FIG. 2 is an enlarged isometric view thereof; and,

FIG. 3 is an isometric view thereof.

The desktop computer system in FIG. 1 and the mini tower computer system in FIG. 3 are shown in broken lines for illustrative purposes only and form no part of the claimed design. 

The ornamental design for the computer back panel portion, as shown and described. 